Electrical generation is a persistent challenge in downhole drilling environments.
Transmission of power from the surface is often not practicable. Accordingly, mud motors are frequently used to generate downhole power. A mud motor is composed of a rotating member (a rotor) and a stationary member (a stator). Transmitting power between these two components or between the rotor and another device can be challenging.
Typically, slip rings or slip ring assemblies are used to maintain contact between a stationary and a rotating member. Slip rings consist of continuous rings that are attached to one member (stationary or rotating) where the axis of the ring coincides with the axis of rotation. Brushes or spring tabs are located on the other member so that during rotation, the brushes or spring tabs slide on the ring surface.
One of the shortcomings of the slip ring is that friction causes wear, which limits the life of the slip ring. Moreover, the slip ring assembly must be engineered to prevent separation between the slip ring and the brushes or spring tabs. Accordingly, there is a need for a more robust electrical connection.